Air-circulating fireback



Dec. 4, 1928.

W. J. M CAIN AIR CIRCULATING FIREBACK Filed June 11, 1928 Attorneys an; s

j caries.

WILLIAM J; McCAIN, on LIVINGSTON, ALABA A AIR-CIRCULATING FIREBACK.

Application filed :runen, 1928.- Serial No; 224, 43.-

My; invention relates to anair circulating fireback foropen fire places, employed to uti- 'lize more efi'ectively the heat of the fuel burned'in the the place, and has for its object the provision of apparatus of the character designated which shall be simple of design and economical of mantrfactur'e and which shall include means whereby the parts 7 thereof sub e-cted to the greatestheat-may be:

readily replaced.

A further object of my invention isto pro-- videan air circulating fire back for open fire places which; shall include permanent end manifolds and a replace-able central section directly subjectedto the heat of the fire, to

gether with cooperating battles for efteeting circulationof air through the inanifo ld's and'th-e-centra-l sect on.

Air circulating fire'backs, asheretofore known to me, have usually comprised a hollow structure, either set inplacein the fire place and unattached-to:the side walls thereof,or elseperman-ently built-into the masonry of the fire place, The first mentioned type en tails the necessity of making iu1s1ghtly'a1r conduit connections thereto in the fire place and has accordingly not'gone into wide comlVhere the firebaclr 1S perm-as mercial use. ,nently bui t m-to the masonry, the centralyp'ortion' which is subjected to the heat oft hefuel and the gases ofcombust-ron eventually burns out and, in order to replace the burned out p ort1on, 1t has the end 11 ariifolds. Cooperat-ingbaffles are provided in theend' manifolds and in the cen-' t-ral section whereby the most effective heat transfer is obtained between the fire and the air being circulated. Furthermore, the passages formed by the battles in the fire back are of progressively increasing cross sectional areas thereby compensating for the increased 7 volume of the air as it is heated.

A 3 aratus embod 1:19 features of 1n 1nc c n vent on 1s illustrated in the accompanying heretofore been necessaryto dismantle-the masonry of the fire place and drawings, forming a; part of this application, wherein Fig. 1 isakverticalsectional view along the line I*-I of Fig.- 2,

Fig; 2 is a sectional line II II of Fig. l;

Fig; 3-'is a, sectional view of the fire back removed from the fire place, ta en along the line III-'IH of Fig. 2;

Figs. 43, 5 and 6 show separate elevations of the end manifolds and central replaceablesection.

Referring tout-1'16 drawings for abetter understanding; ofmy invention, Ishow-a fire place having the usualm-asonry side walls 10 and-11 and back wall '12. Fuel isbu-rned in the fireplace as ina grate 13.

plan View along the Disposed within the fireplace to'th'e rear F ofthe grate 13 is my improved air circulatingv fire; back which comprises end' manifolds 14" and 16: and a central replaceable section 26. V/here the fire backis being installed in a house being built, the end manifolds 14 and .16 are built into theflmasonryv of" the side walls 10and'1l, thus avoiding:unsightly air inlet andoutl'et connections to the manifold which would necessarily have to; be. in plain view from the room. Leadingto the mani fold 14 is an air inlet conduit! 18 also built" into'th'e masonry and provided with a damp er 19. to regulatethe fi'ow of air into the fire back. Leading from. the upper porticirof" both of 'tlie manifold-s 14and 16*areout1et conduits 21 and'22"whiclrmaylead to any room desired to be heated remote from the fireplace. In Fig; lofthe drawings, the conduit21 is shown leading to a room at the rear of the fireplace, but". this is'for. the purpose of illustration only and sucliconduits may. beled to any desiredplace. v

Each of. the manifoldsj ltandj 16 is pro vided with an overhangingjfiange 2 3 7 which extends across the top and bottom' thereof and to the rear thereof, but does not extend down the front. Interposed between the manifolds 14 and 16 and resting on the flange 23 is a central air heating section 26 through which the air entering the fire back circulates before its exit from the outlet conduits 21 and 22. Preferably, the flanges of the end manifolds extend just through the permanent masonry of the chimney and the joint be tween the central section and the manifolds, at the front, is made tight by a fire brick lining overlapping the joint as shown at 25. When necessary to replace the central sectaon, it is only necessary to remove the fire brick lining, leaving undisturbed the masonry of the chin'mey.

The central section comprises a front, forwardly inclined plate 27 overhanging the grate 13, a top plate 28, a bottom plate 29 and a back plate 31. The front plate 27 is preferably made of cast iron the better to resist the action of the fire and gases of combustion, while the other plates may be made of any suitable metal. The front plate 27 is provided with longitudinally extending grooves 32 and 33 for the reception of baffles 3% and 36 which are secured to the rear plate 31. in any suitable manner. that the arrangen'rt'mt of the b; files is such as to provide transverse passages of progrcssively increasing cross sectional area for the air being heated. V

The manifold 1 f provided with a ballle 37 in alignment with the ba'llle 36 and above the air inlet conduit 18. The manifold 16 is provided with a bafile38 in alignment with the baffle 8 land beneath the outlet conduit 22 so that air entering the apparatus through the inletconduit 18 flows beneath the baffles 36 across the fire back, then back across the baffle 34 to the manifold 14 as shown by the arrows. From the manifold 14 the heated air may leave through the outlet conduit 21 or flow back across the fire back to the outlet conduit 22. In order to regulate the How of air through the outlet conduits, theyare provided with suitable dampers 41, only one of which is shown.

From the foregoing it will be apparent that I have devised an improved air circulating fire back for fire places which is simple of construction and economical of manufacture and wherein means are provided for readily replacing the parts subjected to the heat of the fire and gases of combustion. It will furthermore be apparent that my improved fire back provides for effective heat transfer between the fire and the air being circulated.

lVhile I have shown my invention in but i one form it will be obvious to those skilled in the art that it is not so limited but is susceptible of various changes and modifications without departing from the spirit thereof and I desire therefore that only such limitations it will be observed shall be placed thereupon as are imposed. by the prior art or as are specifically set forth in the appended claims. 7

hat I claim is:

1. In an air circulating fire back for fireplaces, a manifold at each end of the fire back, air conduits connected to the manifolds, and a removable heat transfer section interposed between the manifolds.

2. In an air circulating fir e back for fireplaces, a pair of end manifolds remote from the fire, a hollow central removable section subjected to the heat of the fire, air inlet and outlet conduits connected to the manifolds, and cooperating bafiles disposed within the end. manifolds and the central section providing passages for the transverse flow of air through the fire back to the outlet conduits.

3. In an air circulating fire back for fireplaces, a pair of end manifolds remote from the fire, a hollow central removable section subjected to the heat of the fire, a forwardly inclined plate included in the removable section and. overhanging the fuel burning portion of the fireplace, an air inlet conduit connected to the lower portion of one of the manifolds, an air outlet conduit connected to the upper portion of one of the manifolds, and coope 'ating baffles disposed within the end manifolds and the central sectionproviding passages of increasing cross sectionalarea for the transverse flow of air through the fire back to the outlet conduits.

l. In an air circulating fire back for fireplaces, a pair of end manifolds embedded in the side masonry of the fireplace and each having a supporting flange projecting into the fireplace, a hollow removable central section resting on the supporting flanges, afor wardly inclined plate overhanging the fuel burning portion of the fireplace, an air inlet conduit connected to the lower portion of one of the manifolds, an air outlet conduit connected to the upper portion of one of the manifolds and leadingto a place to be heated remote from the fireplace, and cooperating baffles disposed within the end manifolds and the central section and arranged to provide passages of increasing cross sectional area for the transverse flow of air through the fire hack to the outlet conduits.

In testimony whereof I affix my signature.

WILLIAM J. MoGAIN. 

